Electric striking mechanism



April 17, 1928.

S. ROLLIN ELECTRIC STRIKING MECHANISM Filed March 8, 1927 3 Sheets-Sheet 1 S. ROLLIN ELECTRIC STRIKING MECHANISM Filed March a, 1927 3 shoets shoet 2 J Rel/AN April 17, 1928.

s. ROLLIN ELECTRIC sw ruxme MECHANISM Filed larch 8, 1927 3 Sheets-Sheet 3 Ill Pateriited Apr. 17, 1928.

UNITED STATES SIMON ROLLIN, OF

TULLE, FRANCE, ASSIGNOR TO SOCIETE ANONYIE DES ANCIENI ETABLISSEMWTS HATOT, O1 PARIS, FRANCE.

ELECTRIC STBIKING MECHANISM. I

Application filed March 8, 1827, Serial No. 178,756, and in France latch 18, 1886.

It has already been proposed to provide clocks with electric stri ring mechanisms by replacing the driving spring by an electric supply feeding an electromagnet controlling the striking lever. In order to obtain the desired number of beats, mechanisms have been devised which allow a given number of spaced electric impulses to be sent into the electromagnet. The passage of the current is controlled by parts of the clock which determine the starting of the striking mechanism. and the rhytlnn'and number of beats. In particular it has been proposed tocontrol the rhythm of the beats by a periodical switch actuated by the pendulum in view of obtaining thus a regular spacing of the beats. The sending of the current impulses is determined by the closing and opening of other electric switches inserted in series in the circuit or by means of suitable devices which control the periodic actuation by the pendulum of the above mentioned periodical switch.

\Vith this system, the current impulses were heretofore always directed in the same direction and the armature of the electromagnet makes the striking lever strike when the current passes; this armature returns then to its initialposition through the action of a spring when the current is interrupted. To obtain this result, electromagnets are used with nonpolarized soft iron armatures.

My invention consists primarily in the replacement of the above mentioned periodical switch which controls the striking mechanism by a reversing; switch feeding an electromagnet the armature of which is polarized by a permanent magnet. The movable art of this electromagnet is secured to or is integral with the striking mechanism to which is given a reciprocating movement having the same magnitude as that of the usual mechanical bells.

This arrangement shows in particular the following advantages.

l.-The electromagnets polarized by a permanent magnet behave like magneto electric motors and have a greater efiiciency than the nonpolarized electromagnets. Experience shows it is possible to obtain thusstronger beats with a smaller consumption of current.

2.The polarized electromagnets allow an important angular movement of the striking lever to be obtained without any intermediate transmission and Without an minimizing of the electric efliciency. x erience shows this provides a pleasing 3.With nonpolarized electromagnets if the contact is not a very clear one, the armature has a tendency to return to its original position under the action of the spring and to vibrate; the sound obtained is not pleasing. These very troublesome vibrations are produced in' particular if the periodical switch has a rubbing contact surface. In this case experience shows the vibrations of the electric contact parts cause small interruptions of the current and thus produce a faulty working of the striking mechan' m.

This drawback is suppressed wit-h t e use of a polarized electroma net. In this case the small interruptions 0% the circuit do not show a tendency of bringing back the lever so that the latter always strikes boldly. It is only when an impulse of opposite direction is allowed that the armature moves back. 'lhus rubbing contacts can be used which work in a much securer manner than mere bearing contacts. This is very important because of the comparatively intense current which is to be cut and which rapidly deteriorates non-rubbing contacts such as were preferably used in the arrangements known heretofore.

My invention relates also to an advantageous form of execution of the parts which provides an accurate release of the striking mechanism and cause the suitable beats to be made at hours and half hours. Their manner of working is such as will allow no mechanical resistance to be caused by the current distributor except when the clock is striking, the pendulum oscillating freely after the beats. The said parts have a very reliable manner of working and can be used separately with ordinary arrangements comprising nonpolarized electromagnets and a periodical switch instead of a reversing switch.

My invention will be well understood by the following description given by way of example and by the corresponding appended drawings.

Fig. 1 is a front view of the striking mechanism secured to a plate.

Fig. 2 is a rear view of the striking mechanism showing the electromagnet, the striking part and the pendulum. Fig. 3 is a side view.

Fig. 4 is a plan view of the electromagnet and of its armature.

Fig. 5 shows on a larger scale the switch as seen from the front.

Fig. 6 is a horizontal section through line 66 of Fig. 3.

Figs. 7 and 8 are two diagrammatical views of the reversing switch in its extreme positions.

Fi e. 9 and 10 are two detail views showing the contacts of the reversing switch.

Figs. 11 to inclusively are explanatory diagrams of the rack and snail mechanism seen from front and side in different positions.

Figs. 16 and 17 are a side and a front view of the releasing device.

The whole electric striking mechanism is mounted on two plates 1 and 2 similar to the plates which support the usual clockworks. At the rear of the device is the pendulum 3 which acts through the finger 4 secured to a vertically adjustable slide on a fork 6, secured to a spindle 7 (Fig. 3) passing freely through the two plates 1 and 2 the front of which bears the reversin switch 8. I v

This reversing switch com rises two insulated contact parts 9-10 igs. 5 to 10). preferably of silver. The part 9 is screwed at 15 on an insulating drum 11 forced at 12 over the spindle 7 and secured to the collar 13 thereof by the pin or rivet 14.

The contact part 10 isforced over the.

grooved end of the spindle 7. The front of part 9 shows a hemispheric portion of which a pivot 16 forms an extension. This pivot bears a socket 17 to which is secured in the usual manner the inner end of a spiral spring 18 the other end of which is secured through a pin 19 to the end of the bridgepiece 20 (Figs. 5 and 6).

This bridge piece 20, preferably of brass, is screwed to the insulating part 21 borne by the plate 1. The screw connecting parts 20 and 21 serves as a circuit terminal and is connected through wire 26 with one of the terminals of a battery or other current sup 1y.

The part 21 bears two very yielding springs 2223 ending with the brushes 24 and 25 (Fig. 5). adapted to come against the contact parts 9 and 10. These springs are secured to squares held by screws serving as terminals for wires leading to the terminals of an electromagnet 68-70.

The bridge piece 20 is provided with an armNZZ to the end of which is pivotally secured av-as lever 29 of insulating material showing two cam like projections. Each of these is. provided with an extensionconstituted by a pin 29 which in the lposition shown in full lines on Figs. 1 and 5 eeps the brushes 24 and 25 away from the contact parts of the switch 8.

The rear part of the cam lever 29 bears throiigh a pin 30 on the top 31 of the detent 32 igs. 1 and 5) pivotally secured at 33 to the late 1. The movement of the detent 32 is limited by the pin 34 passing through a slot provided at the lower part of the detent.

The lower arm 35 of the detent has its outer end 36 provided with a lateral projection resting on the rack 37 pivoting round the point 38. This rack is secured at 38 to a socket 39 which is braked by an elastic shoe 40 secured to abridge piece 41 borne by the plate 1. The socket 39 is also secured to an arm 43 integral with a long incurved portion 44 restin on one of the spirals forming the perip ery of the snail 45; this snail is keyed to the same shaft as the toothed wheel 46 of the clockwork which makes one revolution per 24 hours.

Behind the wheel 46 is the wheel 59 making one revolution per hour and to which are secured two pins 8283 unequally spaced with reference to the center of the wheel (see Figs. 13 and 16).

The rack 37 is provided with fifteen teeth, the last of which 42 is disposed at the lower end of the rack and pro ects less than the others. This tooth as shown on Fig. 1 is held back by the catch 47 pivotally secured at 48 to the plate 1 and constantly urged towards the rack by the spring 49 secured to the bridge piece 50 and acting on the projection 51 provided on the rear end of the catch 47.

A second catch 52 is pivotally secured at 53 to an arm of the lever 54 which is secured. to the middle of the cranked part of a spindle 55 passing round the catch 47 and pivoting inside the bridge piece 56 borne by the plate 1. In the position of rest shown on Fig. 1 the catch 52 is held between the third and fourth tooth of the rack by a spring blade 57 secured on one hand to the back of the catch '52 and bearing on the other on the bevelled end of the lever arm 54.

Moreover a movable detent 58 pivoting round point 58 of plate 1 (see detail views on Figs.,16 and 17) is provided with two bent projections 6061. the free ends of which engage respectively the lower side of the lateral projections 47 and 52 of the catches 47 and 52 (Figs. 1-5 and 16).

At the end of the movable detent are provided:

1.A small arm 62 pointing upwards forming an acute angle with the detent and ending with a bent part 63 which forms a substantially horizontal resting surface preceded by a slightly incurred ramp 64.

2.--A heel 65 (see Fig. 16) showing a notch 66 adapted to engage the end of the brake 40. This brake controls the rack socket 39 when the latter is urged upwards by the catches.

comprising two coils 68 and 70 mounte on the connecting piece 71 secured'to the north pole of the permanent magnet 72. The (3011s 68 and 70 are connected throu h a wire to the brushes 24 and 25 of t e reversing switch.

The poles of the electromagnet are provided with extensions 73-74 between wh ch can move the end 75 of the armature which is pivotally secured to the above-mentioned bent spindle or crank 55 which passes through both plates 1 and 2. The other end 77 of the armature is bent at right anles so as to form a pallet adapted to move 1n front of the south pole of the permanent magnet 72 shown in dot-and-dash lines on Fig. 2.

The spindle 55 also bears the bent rod 78 of the striker 79 acting on the bell 80 borne by the support 81.

To the plate 2 is also pivotally secured a preferably silver spring 84 (Figs. 2, 3 and 6) the free end of which bears against the end of a tapped cover 85 screwed over the' end of the spindle 7 bearing the contact 10. This spring 84 is connected through the wire 86 with the negative pole of the batter The working of the striking mechanism is the following.

The reversing switch oscillates constantly under the action of the pendulum whereas the pinion 59 which bears the minute handle rotates in the direction of the arrow f (Fig. 16) and makes one revolution per hour. When the pin 82 arrives under the heel 66, it lifts the detent 58 which arrives in the position shown in dotted lines, the heel 66 lifts the brake 40 whilst the lateral projections on the catches 47 and 52 slide along the ramps of the bent projections The catch 47 moves slightly. aside and escapes from the first tooth of the rack which is less long than the others; the rack falls through its weight and is prevented from moving any further b its second tooth which is longer and which rests then on the end of the catch 47. This position corresponds to the preparation of the half hour strike.

The movable detent 58 occupies then a position such as will cause the end 63 of the arm 62 to come and remain in its higher position 63 in contact with the projection 36 on the lower end of the detent 32 (Fig. 16) thus replacing the rack 37 which is fallen.

The minute-hand pinion 59 continuing its rotation, the pin 82 is released by the heel the detent 58 returns to its original position shown in full lines on Fig. 16 and the catches 47 and 52 are urged against the rack teeth by their springs. The arm 35 being no longer held by the part 63 falls whereby the detent 31 pivots and ceases bearing the cam lever 29, which pivots. The projections 29 no lon er hold the brushes 24 and 25 apart and the said brushes come into contact with the switch 8.

When the brush 24 is in contact with the part 9 and the brush 25 with the part 10 (Fig. 7) the current produces a north pole in 73 in front of the coil 68 and a south pole in 74 in front of the coil by reason of the direction of the coils winding. The armature which is magnetized as a south pole by influence from the permanent magnet is drawn upwards (position shown in dot-and-dash lines on Fig. 2). As the armature is secured to the spindle 55, the said spindle rocks by an angle such as will make the crank part 55 of the spin:

dle be lowered (Fig. 4) and therewith the catch 52 which descends by a height equal tothe distance between two teeth of the rack; at the same time the striker 79 is removed away from the bell 80.

At the next oscillation of the pendulum 3 the switch 8 is brought back into the position shown on Fig. 8, i. e. the parts 9 and 10 are respectively in contact with the brushes 25 and 24. The current is reversed in the electromagnet and the armature returns into its original position (shown in full lines on Figs. 2 and 14). The striker 79 strikes the bell whilst the crank 55 of the spindle 55 lifts the catch 52 which raises the racks; the catch 47 comes back under the last tooth of the rack, the half-hour strike being thus effected.

The minute hand wheel 59 continuing its rotation, the pin 83 raises again the heel 65. As explained above, this pin is removed further from the center of the wheel 59 than the pin 82. The result is that the heel 65 is raised to a greater degree than in the precedent case whereby the magnitude of the movement of the movable detent 58 is greater as shown in dot-and-dash lines on Fig. 16. In this position the end 63 of the movable detent passes beyond the bent extremity 36 of the arm 35 which slides along the slope 64 of the arm 62.

The catches 47. and 52 are moved more apart by the projecting parts 6061 (Fig. 14 in dotted lines) and are completely released from the rack teeth. The rack falls and draws along with it the arm 43 until the part 44 comes against one of the peripheric spires of the snail (Fig. 12).

As the height of each spire corresponds to a given number of teeth of the rack between one and twelve, the part 44 is prevented moving by the spire of the snail Hill which corresponds to the time given out by k the hour hand on the spindle of which the said snail is secured; th1s spire corresponds thereby to the number of strokes to be made. On Figs. 11 and 12 the snail is placed in a position corresponding to 9 oclock shown by the small hand. The radius of the spire against which the part 44 abuts is such as will provide a fall of the rack by 9 teeth.

The minute hand wheel 59 continuing to rotate the pin 83 releases the heel 65 of the detent 58 which returns to its original position whilst the catches 52 and 47 come into the position shown on Fig. 11. The detent 32 moves downwards and as before the brushes 24 and 25 are allowed to come into contact with the segments 9 and 10 of the switch 8. a

Each time the switch 8 reverses the current in the electromagnet, the armature 75 and the spindle 53 will oscillate; each time the catch 52 is raised when the striker strikes the bell, the rack will be raised by one tooth until it is returned into its original position wherein it lifts through the arm 37 the lower .part of the detent 32 which in its turn acts on the lever 29 whereby the switch brushes are moved aside and the current is interrupted.

Evidently detail modifications can be brought to the invention as described hereinabove, without widening its scope. In particular the shape and arran ement of the parts described and shown can e modified according to the intended use of the device and to the space allowed for the parts thereof.

The following modifications may be of interest:

1.The switch may be controlled by any device other than the one described by way of example. For instance the spindle of the reversing disc may be provided with an arm to the end of which is pivotally secured a connecting rod the other end of which pivots on a part securedjto the pendulum. The reciprocating movement of the pendulum can thus be transmitted and produce reciprocating movement of the switch.

fi -Instead of a. reciprocating switch, a rotating switch controlled by the pendulum may be used. Such a switch may be secured to the ratchet wheel of the clock or else be integral with another ratchet wheel driven by the pedulum through a catch. This rotating switch may show insulating sectors whereby the interval between the beats of the striking mechanism is a multiple of the period of the oscillations of the pendulum.

The abovedescribed parts which release the striking mechanism and stop it when the required number of beats is. made may be used with a striking mechanism comprising a non-polarized electromagnet controlled by an intermittent current owing always in the same direction. The switch may be constituted by a small reciprocating or rotating switch which comprises insulatlng and conducting parts, the said parts passing alternatingly in front of an elastic blade normally held away from the disc. This blade comes into. contact with the disc durin the striking period through the action 0 the same parts as in the abovedescribed device.

The clock provided with the abovedisclosed striking mechanism can be used as a masterclock controlling from a distance independent striking mechanisms working simultaneously or the striking mechanisms of controlled clocks. In view of this the controlled striking mechanisms may be constituted by electromagnets connected in series with the electromagnet of the masterclock constituted as described. Thus the armatures of all the electromagnets will move and stop simultaneously.

What I claim is:

1. .An electric striking mechanism for clocks comprising the clock pendulum, a reversing switch actuated'by the pendulum, a

polarized electromagnet, means whereby the switch is adapted to send current of alternatingly opposite direction into the electromagnet, during the striking period, the pivoting armature of the electromagnet, a striker secured thereto, a bell disposed in the path of the striker, means whereby the electromagnet when fed by current of a given direction moves the striker towards the bell and when fed by current of opposite direction moves it away from the bell, and an arrangement for controlling the number of beats of the striking mechanism.

2. In an electric striking mechanism as claimed in claim 1, a reversing switch comprising two segments, a current supply each terminal of which is connected with one of the segments and means whereby the pendulum gives the switch a periodic move ment.

3. In an electric striking mechanism as claimed in claim 1, a reversing switch comprising two segments, a current supply each terminal of which is connected with one of the segments, means whereby the pendulum gives the switch a periodic movement, two brushes connected with the electromagnet and adapted to rub on the said segments,

away from the segments out of striking period, a detent keeping normally said cam in its operative position, a rack forming part of the arrangement controlling the number of beats and adapted to release the detent, means whereby the rack is controlled by the minute hand wheel of the clock and means whereby the detent is held in its operative position until the rack has fallen in its lowerposition.

5. In an electric striking mechanism as claimed in claim 1, a rei ersing switch comprising two segments, a current supply each terminal of which is connected with one of the segments, means whereby the pendulum gives the switch a periodic movement, two brushes connected with the electromagnet and adapted to rub on the said segments, springs urging them against the segments, a double cam adapted to hold the brushes away from the segments out of striking period, a detent actuating said cam, a rack forming part of the arrangement controlling the number of beats and controlling the detent, a snail also forming part of the said arrangement and driven by the clockwork, a stop secured to the rack and adapted to bear against the snail and means whereby the rack is controlled by the minute hand wheel of the clock.

6. In an electric striking mechanism as claimed in claim 1, a reversing switch comprising two segments, a current supply each terminal of which is connected with one of the segments, means whereby the pendulum gives the switch a periodic movement, two brushes connected with the electromagnet and adapted to rub on the said segments, springs urging them against the segments, a double cam adapted to hold the brushes away from the segments out of striking period, a detent actuating said cam, a rack forming part of the arrangement controlling the number of beats and controlling the detent, a snail also forming part of the said arrangement and driven by the clockwork, a stop secured to the rack and adapted to bear-against the snail, means whereby the rack is controlled by the minute hand wheel of the clock, a crank to which is keyed the electromagnet armature, and a catch keyed to said crank and adapted to raise the rack by one tooth after each beat.

7. In an electric striking mechanism as claimed in claim 1, a reversing switch comprising two segments, a current supply each terminal of which is connected with one of the segments, means whereby the pendulum gives the switch a periodic movement, two brushes connected with the electromagnet and adapted to rub on the said segments, springs urging them against the segments,a double cam adapted to hold the brushes away from the segments, out of striking period, a detent actuating said cam, a rack controlling the cam, the lowest tooth of which is shorter than the other a snail driven by the clockwork, a stop secured to the rack and adapted to bear against the snail, means whereby the rack is controlled by the minute hand wheel of the clock, a crank to which is keyed the electromagnet armature, a catch keyed to said crank and adapted to raise the rack by one tooth after each beat, a second catch adapted to engage the lowest tooth of the rack, and means whereby the minute hand wheel releases partly the last mentioned catch at half hours.

In testimony whereof I have afiixed my signature.

SIMON ROLLKIN. 

